load: support loading images with different providers (podman)

[flouthoc]

As of now kind hardcodes looking and loading images from docker
as a result kind load docker-image <image>:<tag> does not works well when
Provider is configured as podman instead of docker.

Following PR makes sure that kind supports loading images irrespective of
the providers configured and works for both podman and docker

Closes: #2729

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[APPROVALNOTIFIER] This PR is NOT APPROVED

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[flouthoc]

Created a bug so it can be tracked even if PR is closed: #2729

[BenTheElder]

#2729 (comment)

[BenTheElder]

1. this is a breaking change, some projects like kubernetes require docker to build images, but the user may opt to create the cluster with podman (it's possible to install both), after this change loading the images would no longer work. there's an outline for a new unified image load command in unified image loading: podman/docker/nerdctl/tarball #2038
2. image saving isn't necessarily a property of node providers, we should not move it there as discussed in unified image loading: podman/docker/nerdctl/tarball #2038, you could imagine a provider using say ingnite, kubectl pods or other where we can still run containers but not obtain images, and I should really be able to load across docker image x podman nodes and podman build x docker nodes (it's admittedly likely niche, but we might as well make it simple to handle because someone is going to want this and it shouldn't be difficult to implement or maintain).

[flouthoc]

Closing this until there is a final design discussed in upstream and this is not a blocker for my use-case so this can wait.